PREVENTER FOR WELL WITH INCLINED MOUTH AND TWO-ROW STRING Russian patent published in 2020 - IPC E21B33/06 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to sealing equipment of wellheads of oil and gas wells during their operation and repair in order to ensure safety, prevention and elimination of oil, gas and water ingress (OGWI), including at ultraviscous oil (UVO) wells with inclined mouth and two-row string, protection of entrails and environment. Preventer for well with inclined mouth and two-row string includes upper and lower flanges, housing equipped with vertical circular axial channel, first side horizontal channels made in housing, in which ram blocks are installed with possibility of longitudinal movement, in ram blocks there are pipe rams equipped with elastic seals, and manual drives of rams control, including driving rods of rams, having threaded connections for interaction with covers screwed into housing, at that cavities of housings of ram blocks in cross section have rectangular shape, and elastic seals are arranged in slots made in tube rams, second lateral horizontal channels made in upper flange, which in tightly arranged from outside screwed side screw stops, interacting with sliding sliders, which are equipped with key slots, wherein side horizontal channels are located symmetrically relative to axial channel, longitudinal axes of side horizontal channels are located perpendicular to axis of vertical channel, wherein upper flange is equipped with keys, installed in key slots of sliding slides, having the possibility of longitudinal movement within key slots, connecting and sealing dimensions of lower flange of ram preventer are made corresponding to that of support flange of wellhead equipment, on which ram preventer is fixed, and elastic seals are made of heat-resistant rubber. Pipe rams of ram blocks in first horizontal channels are equipped with front slots with semi-ring recesses, in which heat resistant elastic seals are fixed, which seal pipe string of larger diameter. In the second horizontal channels there are sliding slides with additional tube rams equipped with slots with semi-ring recesses, in which heat resistant elastic seals are fixed, which seal the pipe string of smaller diameter. Centering bushing is fitted at the bottom from the casing axial channel and equipped with two parallel vertical cylindrical channels of larger and smaller diameters. Inner diameters of vertical cylindrical channels are 4-6 mm larger than maximum outer diameters of larger and smaller tubing string lowered simultaneously in inclined well. Central axis of semi-ring recesses of tube rams in closed state is coaxial with central axis of vertical cylindrical channel of larger diameter. Central axis of semi-ring samples of additional tube rams in closed state is coaxial with central axis of vertical cylindrical channel of smaller diameter. Aforesaid distance between semi-ring recesses of tube rams and semi-ring recesses of additional pipe rams, as well as interaxle distance between central axes of vertical cylindrical channels of larger and smaller diameters are equal to each other.

EFFECT: preventer for wells with inclined wellhead and double-row pipe string allows to expand technological capabilities, to improve quality of pipe string sealing in case of OGWI occurrence, higher safety of operations at the wellhead of UVO inclined wells at OGWI occurrence, reduced duration of downhill lifting operations, since pipe strings are lowered into the well sequentially.

1 cl, 5 dwg